condition mean min max ZT0-3 12.411585 12.411585 12.411585 ZT4-7 13.6822055 13.6822055 13.6822055 ZT8-11 13.596238 13.596238 13.596238 ZT12-15 13.8078055 13.8078055 13.8078055 ZT16-19 13.0178905 13.0178905 13.0178905 ZT20-23 13.871717499999999 13.871717499999999 13.871717499999999